Recent studies have provided evidence to support a causal relationship between asthma exacerbations and exposure to inflammatory agents such as endotoxin and fungal glucans. Investigators have also begun to assess what changes to the environment can reduce the severity of asthma. This project is a community- based, participatory, environmental intervention study in an established cohort of asthmatic children who reside in a rural, medically underserved, and ethnically diverse Iowa county. The cohort is currently serving as the control group for a medical intervention in the adjacent county. This project recognizes that interventions that are effective for urban residents may not apply to children living on farms and in rura1 communities. Thus, this project will test the efficacy of an intervention that includes a household hygiene educational intervention, professional super cleaning, booster cleaning, and integrated pest control against a minimal intervention in the control group. This randomized controlled study with repeated measures has the following specific aims: Aim 1. Develop and validate reproducible, quantitative methods for assessing airborne and settled dust exposures to inflammatory agents and rural allergens in homes and schools. Aim 2. Perform a pilot study to establish the time course for changes in environmental concentrations of etiologic agents before and at various times after an extensive "Super Cleaning." Aim 3. Perform a controlled, targeted environmental intervention in homes and schools of 132 rural child asthmatics and determine the effectiveness of these measures for reducing exposures to etiologic agents for asthma. Aim 4. Determine the effectiveness of the asthma intervention measures for reducing asthma symptoms, school absenteeism, and utilization of medical services; and improving pulmonary function and quality of life. Aim 5. Through analysis of pre-intervention and post-intervention exposure data and health status data, examine exposure-response relationships between endotoxins, glucans, and other exposure and indicators of health status. Environmental sampling in the homes will occur at baseline and 6, 14, and 26 weeks. Home hygiene education will occur at 2 weeks, the professional super cleaning will take the place at 4 weeks, follow-up home hygiene educations at 6 and 14 weeks, and the booster cleaning at 16 weeks. Detailed health and home hygiene questionnaires and home inspections will be conducted at baseline and one year later, as will child spirometry.